1. Technical Field
The present disclosure relates to a surgical fastener apparatus including a handle assembly and a disposable loading unit mountable relative to the handle assembly. More particularly, the present disclosure relates to a fastener apparatus having an activation mechanism to confirm and facilitate proper sequential mounting of multiple loading units relative to the handle assembly.
2. Background of Related Art
Surgical fastener apparatuses for applying fasteners or staples to tissue are well known. These fastener apparatuses include single use devices which are preloaded with one or more staples and are disposable after a single use. Multiple use devices are also available and are preloaded with a plurality of staples. Multiple use devices are disposable after the supply of staples has been exhausted or a surgical procedure has been completed. If the supply of staples is exhausted prior to completion of a surgical procedure, a new device may be required to complete the surgical procedure. The use of additional devices for a single surgical procedure can be expensive.
Covidien, LP, has manufactured and marketed stapling systems having replaceable cartridges, such as the Multifire ENDO GIA™ 30 and Multifire ENDO GIA™ 60 systems, for a number of years. These systems include an electromechanical handle assembly and a surgical loading unit. The loading unit may be a single use loading unit (SULU) or a multiple use loading unit (MULU). The loading unit includes a body and an end effector, and is attached to the handle assembly, and/or an adapter assembly associated with the handle assembly, immediately prior to surgery. The end effector may include a cartridge which houses a plurality of staples. After use, the loading unit can be removed relative to the adapter assembly and replaced with a new loading unit to perform additional stapling and/or cutting operations. A drive assembly is supported within the loading unit and is engagable with an associated drive mechanism of the adapter assembly to control operation of the loading unit.
Although these systems have provided significant clinical benefits, improvements are still possible. For example, since the handle and adapter assemblies are reusable it would be desirable to incorporate a mechanism which facilitates proper and repetitive coupling of the loading units to the adapter assembly without degradation of the mechanical or electrical operating components.